High-performance p-n heterojunction photodetectors based on V2O5 nanorods by spray pyrolysis

V2O5 heterojunction photodetector was fabricated onto Si(100) substrate using spray pyrolysis technique. Vanadium chloride (VCl3) precursor with 0.05 M concentration was used to prepare V2O5 thin film. The structural, morphological, and optical properties of V2O5 thin film were investigated. High-resolution X-ray diffraction analysis confirmed the formation of V2O5 thin film with a preferred orientation along (110) plane. Morphological observations using field emission scanning electron microscope displayed the formation of thin film with rod-like nanostructure. The optical properties examined by photoluminescence spectroscopy indicated a high-intensity visible peak centered around 530 nm. Current-voltage (I-V) characteristics of the fabricated device under visible light exhibited low dark current and high photocurrent of 540 mu A at 3 V bias voltages. Upon exposure to 560 nm visible light (24 mW/cm(2)) at 3 V, the device displayed a good sensitivity of 20.16 X 10(2). In addition, the internal gain of the photodiode was 21.16, and the photoresponse peak was 50 mA/W. The rise and recovery times of the photodiode were calculated to be 0.127 and 0.526 s under visible light (560 nm, 24 mW/cm(2)), respectively, at 3 V.